Monthly Archives: May 2013

“Stuff is stuff, and energy is energy, and in Newton’s world, ‘never the twain shall meet.'”

I like these words. Michael Doyle wrote them in his post Food is not energy and they stick with me. Stuff makes sense to my students. They bang their desks, rip up paper, sit in chairs. Stuff – when they see it – makes sense. Energy challenges me and for my students the word “energy” means all sorts of different things.

From the Next Generation Science Standards, the following expectations are given to middle school teachers regarding the flow of matter and energy through ecosystems and the role of photosynthesis in these processes.

Students who demonstrate understanding can:

MS-LS1-6.

Construct a scientific explanation based on evidence for the role of photosynthesis in the cycling of matter and flow of energy into and out of organisms. [Clarification Statement: Emphasis is on tracing movement of matter and flow of energy.] [Assessment Boundary: Assessment does not include the biochemical mechanisms of photosynthesis.]

MS-LS1-7.

Develop a model to describe how food is rearranged through chemical reactions forming new molecules that support growth and/or release energy as this matter moves through an organism. [Clarification Statement: Emphasis is on describing that molecules are broken apart and put back together and that in this process, energy is released.] [Assessment Boundary: Assessment does not include details of the chemical reactions for photosynthesis or respiration.]

MS-LS2-3.

Develop a model to describe the cycling of matter and flow of energy among living and nonliving parts of an ecosystem. [Clarification Statement: Emphasis is on describing the conservation of matter and flow of energy into and out of various ecosystems, and on defining the boundaries of the system.] [Assessment Boundary: Assessment does not include the use of chemical reactions to describe the processes.]

Whew! That’s a load on these middle schoolers. Take a step back for a moment to think about your understanding of these topics. Then, watch this video by Derek Muller at Veritasium. Where would you position your thoughts? The thoughts of your students?

It’s the end of the year and I would like to say that my students have developed a strong foundation surrounding energy and mass. I would like to say that when posed with the question Where do trees get their mass from? my students would not only provide an answer but also an explanation involving processes. But, it’s a stretch and most are not there.

What have we done? We’ve planted seeds in the garden. We’ve planted seeds in the class. We’ve watched plants grow; noting the lack of depressions around both our new seedlings and older, established plants. Whoa, the plants are not eating the soil. We’ve put plastic bags around plants to capture water from transpiration. We’ve done skits, drawn diagrams, had big group talks, enjoyed small group talks. We’ve watched videos. We looked at cells and talked about digestion and respiration. It’s a topic we’ve returned to time and time again. But, they are shaky.

Soil they see. Water they see. Sunlight they see. Air? Nope. Carbon dioxide in air? Hmmm…

So, I’m back to the theme of No Matter How Many Times You Explain Something and I know that me standing in front of the classroom yapping about energy and matter is not what will push my students to a deeper understanding. What’s next? I guess I’m seeking ideas on moving forward and -can this be done – I want a Bacon-Wrapped Unit to help out. (Bacon-Wrapped Lessons are Shawn Cornally’s brain child to bring teachers, students and parents together to “smoke out the best lessons possible” on those difficult standards.) What does it take to make a powerful shift in the ideas of our students? Here’s a topic that has shown its difficulty in being understood yet is “expected” of young teenagers. Suggestions? Comments?

Postscript:

Towards the end of the day, I had a conversation with one of my classes. I showed them my blog and explained that I try to reflect on my work through writing and sharing as they often do in class. I shared with them this issue of shifting mind sets and asked what they thought about and what they believed that they needed in order to shift. Interestingly, the students how do seem capable of adjusting previous conceptions responded along the lines of needing a shared experience or needing to work out proof for themselves. The students who struggle wrote that they need to read from a book or ask a parent.

Summer is around the corner and many international teachers look forward to returning to that place called home. Personally, I eagerly await my summer visit to the Pacific Northwest.

Punchbowl Falls on Eagle Creek, Columbia River Gorge

As an engineer, I moved to Los Angeles; Huntington, WV; Raleigh, NC; and Portland, OR to start new jobs. Each time, an orientation was followed by a slowly ramping up of responsibilities. Learn the processes, the work flow, the people and begin contributing. Meanwhile, I found it easy to get my home life up and running. Bank accounts transferred and language barriers did not exist as I obtained a phone, places to live, utilities, groceries and almost anything else.

Teaching is different. On the first day of school, students are nervous yet ready to begin. The fact that my life may be in a crazy state of turmoil is low on their radar. I’m the new teacher and I have to hit the ground running. There is no slow ramp up with students. A sweet spot exists at the beginning of the year. Who is the new guy? What is he like? Is he up for us? International teaching adds an additional twist. Not only is there a new batch of students, a new grade level, new coworkers, new procedures but life outside of school must be established. This can be difficult with language barriers and process that are different from the States. For example, in Taiwan little can be accomplished without the Alien Resident Card, which takes several weeks to obtain. As we move to China, our belongings must wait for us to clear customs before they can arrive. This means that our household summers in Taiwan longer than we do and will arrive in Beijing weeks after us.

So far, the transition to China seems to be moving along smoothly. Our new school is doing a fantastic job communicating with us and making us feel part of the community. I’m curious as to how people transition to new jobs and cultures. What do you do? A retired US ambassador recently talked at my school and when he was finished his wife gave a few words. She said her goal was to establish “home” as soon as possible. Once home was set and the family felt stable everything else could continue. This is our first big move with children. Advice? Thoughts?

Students came into my class to see the comic above projected on the screen. The comic reminds me of frustrations at my grandmother’s house trying to get the temperature just right. A slight adjustment would either freeze or scald me. My students looked with blank expressions. It seems as if none of them have this experience. Given the homes of many, I wonder if they simply program in the water temperature of choice. What are they missing from this daily experiment?

With the comic intro a flop, I asked each to individually answer the following:

Water at two temperatures are mixed together. The two temperatures are 50 C and 10 C. Please make a selection that best fits what you believe will happen to the temperature once they are mixed.

The temperature of the “colder” water will be subtracted from the “warmer” water, resulting in a final water temperature of 40 C.

The temperatures of the two waters will be averaged, resulting in a final temperature of 30 C.

The temperatures of the two will be added, resulting in a final temperature of 60 C.

Students were also asked to explain why they chose the subtraction, average or addition conception. In my class of 20 students, an even selection was made with 10 students selecting subtraction and 10 selecting average. For me, the line was almost predictable. Before class, I put students in groups that I anticipated would have similar conceptions. That way students would share initial ideas as they then moved forward and planned an investigation. My predictions were almost spot on.

For me, the interesting information was found in the explanations of reasoning. Support for the subtraction conception:

I believe (a) because when cold hits something hotter it mixes together.Then the cold changes to warm because it mixes with the hot.

a, because there are more heat molecules than cool molecules and they will end up subtracting each other.

I chose “a” because I had mixed hot and cold water before and the temperature dropped.

A. The hot water is too hot that it will break those coldness in cold water. That the water temperature would stay at a higher temperature.

I believe that it is “A” because I made it into real life. When the two waters are mixed, the water is hotter but there is cold water which ends up having a hot water, but it’s colder than the original one.

A, because when the cold water meets the hot water the cold water is not going to become hot water. It is going to mix, so the temperature should become 40C.

You cannot add both of them up because they are like positive and negative numbers. Add more hot water and the water will be warmer.

Support for the average conception:

Because the energy of the hotter water would mix with the colder water and they will get averaged.

The water will cool down until both temperatured water becomes the same temperature.

Because the hot water will heat the cold water up and the cold water will cool the hot water down until they have the same temperature.

There is more energy in the hot water than the cold water. When the hot & cold water mix, the energy evens out so the temperature will be averaged.

B, because I believe the two waters are the same volume (mass) and the temperatures would come together and be divided by 2.

The temperature of the two waters will be averaged if the amount of water on both sides are the same. Temperature is a unit to show an amount of energy. If two energies get mixed, the temperature we get will be their average.

I chose “b” because the two cups of water contains the same amount of water mixed together. After the two cups of water mix together the temperature would be mixed and averaged.

Assuming that both are the same amount, the water mixed would result in 30C. Heat transfers quickly, the cold water drains the hot water’s heat while the hot water has cold temperatures spread through it. Both balance out each other.

I think the best choice is b because neither the cold water or hot water should be subtracted or added into each other so the best choice is to average both.

If the amount of both water is the same, the water will average out. The water is not “negative” or “positive”. There is a colder/hotter temperature for both waters so therefore they will average.

From this point, I asked students to grab a whiteboard to sketch, write a procedure and make a data collection table. The stumbling block on procedures was when to take the final “mixed” temperature. In the end, each of the five groups produced data that supported the average conception.

Where now? Students made a prediction, planned an investigation and collected data. Next class involves making a claim, using evidence to support the claim, and reasoning to tie together their ideas. I’m looking forward to reading the students’ reasoning. They were given background reading that I hope will support the experimental data. Will I be treated with more insight into their thoughts on this concept?